Running Multiple Linux Kernels Without Hypervisor

A new project called multikernel Linux (mklinux) allows multiple independent Linux kernels to run simultaneously on bare metal without a hypervisor, achieving near-perfect isolation and lower latency compared to KVM guests, according to an announcement on LWN.net. The host kernel handles hardware resource allocation, and benchmarks show performance between parity and two times faster than KVM.

In a move that’s no doubt going to trigger a lot of confusion and nostalgia, Mklinux is back https://lwn.net/Articles/1090582/ , in a sense. As the announcement https://lwn.net/ml/all/ao34RJ7aZ2BLd67S@pop-os.localdomain/ makes clear, this is multikernel Linux, not microkernel Linux https://en.wikipedia.org/wiki/MkLinux , which is an experimental OS designed to run the Linux kernel as a user-space server running on top of OS X’s Mach kernel. Naming overlap niggles aside, this neo-mklinux lets multiple independent Linux kernels run simultaneously on bare metal. There is still a host kernel which handles the carving up of hardware resources to the newly spawned kernels, but unlike with a hypervisor there are no abstraction or translation layers. In theory this should mean basically perfect isolation between kernels, which is one of the main selling points along with increased performance. Compared to running KVM guests the provided benchmarks show much lower latency, at between parity to two times faster. A website https://multikernel.io/getting-started.html is provided with instructions to get started, along with architectural details if that’s your thing.